It is often desired to ensure that a multi-engine aircraft is able to achieve takeoff and landing with one engine in the event of one or more engine failures in those and other critical flight modes. If, for example, both engines of a twin engine turboprop aircraft are each operating on takeoff at about 90% of full rated power (a typical fuel saving measure) and one suddenly "dies," control is enhanced by automatically feathering the dead engine and uptrimming the good engine. The feathering might save, for example, approximately 15% drag on the good aircraft and the uptrim, by providing more fuel to the engine, might provide approximately 10% more power for a total effect of approximately 25% more power.
If, however, during takeoff there is a single engine failure followed by a temporary electrical failure, the command to feather the dead engine and uptrim the good engine is lost. Upon return of electrical power, the feather and uptrim conditions are not continued. As a result, the loss of feather would increase the drag by approximately 15% and the loss of uptrim would reduce thrust by approximately 10%.